Adaptation of crops to environment

Adaptability is defined as the ability of a crop (or variety) to respond positively to changes in agricultural conditions. The trait is genetically controlled and provides an ability to exploit environmental attributes, both natural and agronomic. Values of relative adaptability can be determined by the regression of the yield of the tested crop over the average yield of compared crops from several environments. We evaluated relative adaptability of 12 staple crops in 12 European countries and compared the yield data over a 43-year period from 1961 to 2003. An additional set of average yield data was also available for the 15 European Union (EU15) member countries. A wider range of 26 crop species was investigated that allowed comparisons between Europe and the USA between 1961 and 2003. Adaptability was closely related to the annual yield increases of the crops studied (r ²=0.999 both in the EU15 and the USA). However, the adaptability of certain crops differed between the two regions. Pulse, maize, millet, wheat and sorghum showed the highest adaptability in the EU15 region, whereas strawberry, pear, tomato, walnut and maize were highest in the USA. The lowest adaptability was found for walnut, pear, apple, cauliflower and hop in the EU15 and for mustard, hop, sugar beet, millet and oat in the USA. In European countries, crops with similar biology, environment and agronomical practices (like the amount of fertilizers and pesticides applied) tended to have similar adaptability values. The data indicate that high adaptability is an important prerequisite for continued yield gains in the best environments.     

植物次生代谢及其与环境的关系

人类对植物次生代谢产物（天然产物）的早期研究源于它们的应用价值,近些年来人们越来越认识到植物次生代谢产物广泛的生物学效应,开始重新评价这些化合物在植物生命活动以及生态系统中可能扮演的角色。植物的次生代谢是植物在长期进化中与环境（生物的和非生物的）相互作用的结果,次生代谢产物在植物提高自身保护和生存竞争能力、协调与环境关系上充当着重要的角色。介绍了植物次生代谢及其产物的特点,概述了植物次生代谢与温度、水分、光照、养分、CO2浓度、UV-B辐射、环境污染等非生物环境以及与化学防御、化感作用、菌根共生、微生物病害的关系。研究植物次生代谢与环境的关系,可以从更深的层次发掘植物与环境的内在联系,为全面、深入认识植物与环境的相互关系提供新的研究途径,同时也有利于人类更有效、合理地利用植物的次生代谢产物。     

An insight into the sensitivity of maize to photoperiod changes under controlled conditions

Response of maize to photoperiods affects adaption of this crop to environments. We characterize the phenotypes of four temperate‐adapted maize foundation parents, Huangzao 4, Chang 7‐2, Ye 478 and Zheng 58, and two tropically adapted maize foundation parents, M9 and Shuang M9 throughout the growth stage under three constant photoperiod regimes in a daily cycle of 24 h at 28 °C, and analysed expression of 48 photoperiod response‐associated genes. Consequently, long photoperiod (LP) repressed development of the tassels of photoperiod‐sensitive maize lines at V9 stage, and caused subsequent failure in flowering; failure of photoperiod‐sensitive maize lines in flowering under LP was associated with lower expression of flowering‐related genes; photoperiod changes could make a marked impact on spatial layout of maize inflorescence. The larger oscillation amplitude of expression of photoperiod‐responsive genes occurred in LP‐sensitive maize lines. In conclusion, failure in development of tassels at V9 stage under LP is an early indicator for judging photoperiod sensitivity. The adaptation of temperate‐adapted maize lines to LP is due to the better coordination of expression among photoperiod‐sensing genes instead of the loss of the genes. High photoperiod sensitivity of maize is due to high expression of circadian rhythm‐responding genes improperly early in the light.     

植物蜡质及其与环境的关系

陆生植物的地上部分如叶、茎、花、果实等的表面覆盖着一层蜡质,它是由一系列复杂化合物组成的具有三维微结构的疏水层,在植物生长和发育过程中起着不可或缺的作用,具有很好的生物学功能。作为植物与环境的第一接触面,蜡质对外界环境因子的响应较敏感,当植物受到外界不利环境因子胁迫时,蜡质会改变自身晶体结构形态或化学组分构建防御机制以减少胁迫因子的作用,有效地协调植物与环境的关系。综述了近年来国内外关于植物蜡质的研究进展,在阐述蜡质层结构及其化学组分的基础上,着重介绍植物与环境因子的作用,包括非生物环境因子如水分、温度、光照、环境污染等以及植食性昆虫和病原菌等生物环境因子的作用。研究显示,胁迫环境下植物蜡质化学组分的变化,是由于不利环境因子的作用足以改变蜡质各产物的合成途径,从而影响蜡质产物。植物蜡质利用各种生理、化学机制对胁迫环境因子的适应以及响应,是植物适应各种生境的基础,因此通过对植物蜡质与环境关系的研究为进一步解析植物与环境关系提供证据。     

工业对生态环境的影响--以广东顺德市为例

环境问题在程度上是由工业发展引起的。以广东省顺德市为例。环境问题如江河、大气、土壤环境污染等与工业三废排放、工业类型、工类布局、工业能耗等有密切关系。解决对策是实施可持志发展战略,调整优化工业结构,工业合理布局规模经营,推行清洁生产、进行污染治理等。     

Genetic correlation in relation to differences in dosage of a stressor

We exposed the strains of Chlamydomonas isolated from an outbred laboratory population to a range of concentrations of salt (NaCl) up to an extirpative level that the base population could not tolerate. The genetic variance of yield increased with stress over the first half of this range before collapsing to nearly zero. The genetic correlation decreased with environmental distance, whether measured as a difference in dosage or as an environmental variance. This result is consistent with previous studies and provides a basis for interpreting adaptation to a deteriorating environment and the process of evolutionary rescue.     

Plasmid Maintenance Renders Bacteria More Susceptible to Heat Stress

The presence of shuttle plasmid pTS749 in the oral bacterium Streptococcus mutans resulted in growth inhibition under heat stress conditions. This effect was dependent upon the growth stage of the inoculum used to initiate growth. Likewise, the introduction of plasmids containing distinct ori sequences into Escherichia coli also resulted in growth inhibition at elevated temperatures and could be correlated with the plasmid levels within the cells. These results suggest that these plasmids in bacteria render the cells to be more susceptible to heat stress conditions.     

Moving callitrichid monkeys from cages to outside areas

To assess the important aspects of a large area for environmental enrichment, the behavior of families of common marmosets Callithrix jacchus and cotton-top tamarins Saguinus oedipus when in laboratory cages and when in much larger outside areas was compared. All animals avoided areas with little cover. The two tamarin families preferred an indoor cage to a large open area with little cover and consequently only showed a limited range of behavior when outside. When dense cover was provided to the marmoset family, they used this area extensively, showing a wider range of behavior than when in cages and shifting to less active behavior patterns. By feeding marmosets in a central area, it was possible to allow unlimited access to the outside while effectively containing them.     

中国生态环境区划初探

中国生态环境区划初探高密来（中国人民大学区域经济研究所北京１００８７２）ＡｎＡｐｐｒｏａｃｈｔｏｔｈｅＲｅｇｉｏｎａｌｉｚａｔｉｏｎｏｆＥｃｏｌｏｇｉｃａｌＥｎｖｉｒｏｎｍｅｎｔｉｎＣｈｉｎａ．￥ＧａｏＭｉｌａｉ（ＩｎｓｔｉｔｕｔｅｏｆＲｅｇｉｏｎａ...     

Rapid evolutionary adaptation to elevated salt concentrations in pathogenic freshwater bacteria Serratia marcescens

Rapid evolutionary adaptions to new and previously detrimental environmental conditions can increase the risk of invasion by novel pathogens. We tested this hypothesis with a 133‐day‐long evolutionary experiment studying the evolution of the pathogenic Serratia marcescens bacterium at salinity niche boundary and in fluctuating conditions. We found that S. marcescens evolved at harsh (80 g/L) and extreme (100 g/L) salt conditions had clearly improved salt tolerance than those evolved in the other three treatments (ancestral conditions, nonsaline conditions, and fluctuating salt conditions). Evolutionary theories suggest that fastest evolutionary changes could be observed in intermediate selection pressures. Therefore, we originally hypothesized that extreme conditions, such as our 100 g/L salinity treatment, could lead to slower adaptation due to low population sizes. However, no evolutionary differences were observed between populations evolved in harsh and extreme conditions. This suggests that in the study presented here, low population sizes did not prevent evolution in the long run. On the whole, the adaptive potential observed here could be important for the transition of pathogenic S. marcescens bacteria from human‐impacted freshwater environments, such as wastewater treatment plants, to marine habitats, where they are known to infect and kill corals (e.g., through white pox disease).     

耐极端环境真菌对犬小孢子菌及孢子丝菌的拮抗研究

目的 检测极端环境分离出的真菌拮抗临床病原真菌的活性.方法 选用极端环境分离出的24株真菌菌株上清液及菌丝体的提取液,来进行临床病原真菌（孢子丝菌和犬小孢子菌）的拮抗试验,采用M38-A2产孢丝状真菌抗真菌药物敏感性试验方案和E-test纸片扩散法.结果 抑菌圈直径≥1.0 cm,具有较强拮抗孢子丝菌活性的极端环境真菌有8株;抑菌圈直径≥2.0 cm,具有极强拮抗犬小孢子菌的活性的极端环境真菌有1株.两种临床菌株的拮抗试验,90％的拮抗结果相一致.结论 70％极端环境真菌菌株上清液及菌丝体提取液具有拮抗临床病原真菌孢子丝菌和犬小孢子菌的活性.     

Genetic and environmental contributions to prosocial behaviour in 2- to 9-year-old South Korean twins

Although over 50 twin and adoption studies have been performed on the genetic architecture of antisocial behaviour, far fewer studies have investigated prosocial behaviour, and none have done so on a non-western population. The present study examined mothers' ratings of prosocial behaviour in 514 pairs of 2- to 9-year-old South Korean monozygotic and dizygotic twins. Correlational analyses showed a tendency of increasing genetic effects and decreasing shared environmental effects with age although shared family environment effects and the moderating effects of age did not attain statistical significance in model-fitting analyses. The best-fitting model indicated that 55% (95% CI: 45-64%) of the variance in the 2- to 9-year-olds' prosocial behaviour was due to genetic factors and 45% (95% CI: 36-55%) was due to non-shared environmental factors. It is concluded that genetic and environmental influences on prosocial behaviour in young South Koreans are mostly similar to those in western samples.     

The Value of Forests to World Food Security

We assembled information on the contribution and value of forests to world food security. An assessment was made of the role of forests and non-timber products in the food system of developing countries. We estimated that upwards of 300 million people annually earn part or all of their livelihood and food from forests. A total of about $90 billion in non-timber products are harvested each year. Forests also help to protect land, water, and biological resources, and they play an important role in maintaining the productivity of agricultural and environmental systems.     

塑料添加剂向生态环境中的释放与迁移研究进展

塑料废弃物,尤其是粒径小于5 mm的微塑料造成的环境污染问题已引起全球的普遍关注。塑料制品在生产过程中常使用多种添加剂,以提高聚合物的性能并延长其使用寿命。然而,在废弃塑料制品的回收及自然老化过程中,这些添加剂会不断释放出来,对生态环境的安全与人类的健康产生威胁。综述了近年来国内外塑料添加剂的使用情况及其向生态环境释放与迁移等方面的研究进展,具体包括常用塑料添加剂的种类、废弃物塑料回收和塑料老化过程中添加剂向生态环境中的释放与迁移及机制等。未来需要更加关注绿色塑料添加剂的研发、废弃塑料回收工艺的改进以及关于塑料添加剂的释放、在各类环境介质中的迁移转化以及在生态系统各个圈层间的相互作用方面的系统性的研究,并构建相应的迁移模型评估塑料添加剂产生的生态风险。     

A simple device to measure root growth rates

The construction and use of a simple auxanometer is described. With this instrument students can readily and accurately measure root growth rates of intact seedlings. Typical time course data are presented for the effect of ethylene and indole acetic acid on pea root growth.     

甲壳动物的生殖量与环境关系：Ⅰ.枝角类

生殖量是生殖潜力(reproductivepotential)的一个主要标志,也是生态系统(含生产力)和种群生态学(含数量变动)的一个主要内容。它在很大程度上是由遗传因子(基因)决定的,表现在各类动物的生殖量有很